Chess Tactics - Zwischenzug

 Zwischenzug Chess Resources

German "in-between move". An unexpected move tossed into an expected series of moves.

Wikipedia page
 With explanations and examples

BOOKS (FREE)

Forcing Chess Moves The Key to Better Calculation - 38 page PDF

Zwischenzug Chess Articles 

Chess Tactics Simplified: The Zwischenzug! - Nice Article with Examples at Bottom
ZWISCHENZUG: THE TACTICAL PATTERN THAT CAN SAVE YOU - Article with examples
Tactics 101: The Incredible Intermezzo (a.k.a. Zwischenzug) - Nice Article

Zwischenzug: An Unexpected Tactic of Grandmasters - The Chess Journal Article

Zwischenzug - Chess Kid Article w/ Embedded Video

Examples Of Zwischenzug (Games)

  FM Asa Hoffman vs NM Jim West - From Jim West's Blog (Annotated by both players)
  43 Chess Games with a Zwischenzug - From Chessgames.com (Some nicely annotated games here)
  14 Chess Games with a Zwischenzug - From Chessgames.com
In-Between Move Tactic-- OTB Examples - 25 Games Chessgames.com

Lichess Studys

LiChess Zwischenzug Study - Interactive with Several Examples
Zwischenzug - 9 Chapter Study w/ Instruction
Intermediate: Tactics Internalized - Zwischenzug - 5 Chapter Interactive Study

Zwishenzug Video Lessons

Zwischenzug – Winning with in-between moves - 20 Min 
Zwischenzug | Learn & master in-between moves | Intermezzo | Intermediate moves - 14 Min
The Volatility of In-Between Moves - 9 Min  IM John Bartholomew

St. Louis Chess Club Videos

Zugzwang: I'd Prefer Not to Move | Strategy Session with Jonathan Schrantz - 50 Min
Chess for Beginners with GM Ronen Har-Zvi (Intermediate Moves | Forcing Moves) - 32 Min
Chess for Beginners with GM Ronen Har-Zvi (Intermediate Moves) - 27 Min
In-Between Moves and Zwischenzugs - WGM Jennifer Shahade -53 Min
Zwischenzug | Puzzler's Paradise - IM Vitaly Neimer -  35 Min
Zugzwang and Domination | Insane in the Endgame - WGM Sabina Foisor - 59 Min
Intermezzo: Put Your Plans on Hold! | Beginner Breakdown -  61 Min

Chess Lesson # 44: Zwischenzug | Learn & Master In-between Moves | Intermezzo | Intermediate Moves - 14 Min NM Rober Ramirez

Videos of Games

Chess Tactics: Zwischenzug: Lichtenhein vs Morphy - 5 Min
Zwischenzug! || Nakamura vs Carlsen - 10 Min